Reported again by the submitter's colleague at LINET after #223 was
closed: duplicate checking was implemented for vCard and never for LDIF,
so re-importing an address book still leaves a second copy of everything.
That was deliberate at the time -- the matching key was an open question
I did not want to answer alone -- but the answer had already been given
on #174 and I closed the issue without acting on it.
The answer, in the submitter's words: an attribute that *can* change is
fine, because it will not have changed between two imports minutes apart.
An import is not a sync. That makes the `dn` usable -- it is the only
identity the file carries, and Mozilla's schema defines no UID -- and it
needs no guessing at all, unlike the name-plus-email fallback I had been
weighing.
So `uidFromDn` derives a namespaced, stable uid from the distinguished
name, normalised for the case and spacing two exports of one directory
differ in. A card the book already holds under that uid is updated rather
than duplicated, merged the way the vCard import merges: what the file
carries wins, what it does not mention is left alone. Reported as created
and updated, which is the pair that was asked for.
Three things worth knowing:
Matching is per address book, so two customer directories that each hold
a `cn=John Smith` stay two people as long as they are filed separately.
Imported into one book they would merge, which is the one way this can be
wrong and the reason the escape hatch is worth naming.
The look-alike count stays, and now means something narrower: entries
that `dn` matching could not catch -- one whose `dn` moved between
exports, and anything imported before there was a `dn` to match on. Those
are still only counted, never merged.
A file holding two entries under one `dn` is malformed, since a directory
cannot, and now becomes one card instead of two sharing an identity.
FEATURES gains the re-import behaviour for both formats; it documented
neither.
Somebody arriving from SOGo, Thunderbird or an LDAP directory has their
contacts in LDIF, and until now the only way in was vCard.
Nothing on the server reads LDIF, so this reads it here, in two pieces
that are two different problems. `ldif.ts` is RFC 2849 and nothing else:
folded lines, base64 values, case-insensitive attribute names, options,
comments, `version:` headers, change records. It knows no attribute by
name. `mozillaAb.ts` knows the attributes and no syntax -- Mozilla's
address book schema, which is what Thunderbird and SOGo write and what the
issue asks for by name. LDIF says nothing about what any attribute means,
so a file is only readable against a schema, and keeping the two apart is
what would let a second schema be added without touching the reader.
Work and home addresses, which the schema keeps in two separate sets of
attributes, come across as two addresses. So do every phone kind, the
second email, the organisation and its units, job title, nickname, web
pages and the AIM handle. The four custom fields have no equivalent in
JSContact and are appended to the note, labelled as Thunderbird labels
them: keeping something somebody chose to write down is worth more than
the tidiness of dropping it.
An entry with neither a name nor an address is skipped rather than
imported as a blank row that is impossible to identify and tedious to find
again to delete. The distinguished name is not used as the contact's uid:
it says where an entry sat in somebody else's directory.
One import control takes either format and decides by what is in the file
rather than by what it is called, because an address book exported as LDIF
arrives as .ldif, .ldi, .txt or with no extension at all.
Closes#174
jcoffey-dev